1. Field of the Invention
This invention relates generally to improvements in a valve operating system for an internal combustion engine which system is arranged such that rotation of a camshaft is converted through a swing arm to reciprocal movement of intake or exhaust valve, and more particularly to a device for lubricating parts of the valve operating system in order to prevent abnormal wear and damage to the parts.
2. Description of the Prior Art
Internal combustion enignes are provided with a valve operating system for operating intake or exhaust valve to open and close. A variety of the valve operating systems are proposed and put into practical use. For example, an overhead camshaft engine is provided with such a valve operating system that a swing arm is swingably disposed to cause intake or exhaust valve to open or close. The swing arm is driven to swing by a camshaft located over the swing arm and pivotally supported at its one end by a support member such as a hydraulic lifter. The other end of the swing arm is connected to the valve stem of the intake or exhaust valve and adapted to make reciprocal movement of the valve stem of the intake or exhaust valve under swinging movement of the swing arm. In such an engine operating system, there are many contacting and sliding parts which require lubrication. Particularly, the pivotal connection between the swing arm end and the support member requires sufficient lubrication because the pivotal connection is under a severe sliding condition. In this regard, it has been eagerly desired to provide a lubricating device which can effectively lubricate the contacting and sliding sections of the valve operating system particularly a contacting and sliding section between the swing arm and the support member.